The P40 thread

[BlitzPig_EL]

Well, I saw the former Duxford, now Collings Foundation Curtiss P40B today at Thunder Over Michigan.

 

 

And yeah, that's me.

 

I spoke with the pilot for a bit and asked him about how it is to fly.   He said it is very light and responsive on the controls, that it will out roll and out turn a P51, and out roll and probably out turn the Spit Mk IX he also pilots.

 

He also said it a wonderful airplane to fly, until the tailwheel touches the runway, then it turns into a monster... hehe.  Apparently cross winds are an issue for it on the ground.  I asked him about overheating, and he said it's not an issue in the air, but on start up or landing you have to either take off or shut it down really quickly, or it will over heat the coolant.

 

It was really fun to watch in flight,  it's pretty obvious just how effective the ailerons are on it.

 

Oh, this is the only flyable Hawk 81 there is, and it survived the attack on Pearl Harbor...

Edited September 2, 2017 by BlitzPig_EL

[indiaciki]

[VBF-12_Stick-95]

Collins has it now?  Nice.  Not far from there.

[LLv24_SukkaVR]

Nice picture and story. Sometimes i forget how big those things are.

[BlitzPig_EL]

When you are standing there my impression of it was that it was almost dainty compared to a P51 or later model Hawk 87.

 

Of course compared to a point interceptor like a Spit or 109 then yeah it is bigger.

[indiaciki]

@71st_AH_TwoLate

 

If you start on the runway your RPM is 85%. I started paked and gave her 100% RPM on TO. Big mistake. The engine blew up before I took off.

[LukeFF]

One thing that helps with flying the P-40 is setting your fuel level to about 75%. This accounts for the 28 or so gallons that would be used up during the engine's warmup. That's a hefty bit of weight subtracted right there.

[deleted@31403]

@71st_AH_TwoLate

 

If you start on the runway your RPM is 85%. I started paked and gave her 100% RPM on TO. Big mistake. The engine blew up before I took off.

 

 

So keeping engine in normal temps does not guarantee the engine from damage.

Edited September 2, 2017 by 71st_AH_TwoLate

[indiaciki]

No it doesn't. Too much RPM & too much manifold pressure = engine falls apart. Like the Ju-87 & He-111 engine. Just worse. Much worse and quickly.

[Venturi]

Well, I saw the former Duxford, now Collings Foundation Curtiss P40B today at Thunder Over Michigan.

 

 

And yeah, that's me.

 

I spoke with the pilot for a bit and asked him about how it is to fly.   He said it is very light and responsive on the controls, that it will out roll and out turn a P51, and out roll and probably out turn the Spit Mk IX he also pilots.

 

He also said it a wonderful airplane to fly, until the tailwheel touches the runway, then it turns into a monster... hehe.  Apparently cross winds are an issue for it on the ground.  I asked him about overheating, and he said it's not an issue in the air, but on start up or landing you have to either take off or shut it down really quickly, or it will over heat the coolant.

 

It was really fun to watch in flight,  it's pretty obvious just how effective the ailerons are on it.

 

Oh, this is the only flyable Hawk 81 there is, and it survived the attack on Pearl Harbor...

 

Awesome! 

[Field-Ops]

I wonder if the Devs would consider a 100 octane fuel modification once the pacific gets underway, changing the max manifold pressure as well as possibly changing the fuel gauge in the plane to a later one. That would account for both the early war period where the fuel wasnt really around, as well as the late war period where logistics and development caught up.

[Venturi]

One thing that helps with flying the P-40 is setting your fuel level to about 75%. This accounts for the 28 or so gallons that would be used up during the engine's warmup. That's a hefty bit of weight subtracted right there.

 

https://youtu.be/DPxPcbetZhk?t=5m19s Startup at 5:20 into video. At 6:45 into video:  "The P-40 warms up really quickly... we're already at 35C... by the time we're at the end of the runway this thing will be ready to run up." 

 

https://youtu.be/VpMIAPDSaZs 10min after start, takeoff.

 

Hardly 28gal worth of fuel spent there for "warmup". I agree less fuel will help the P-40. I also think cutting out the extra 200lbs from design weight that have been added onto it in the sim would help as well.

Edited September 3, 2017 by Venturi

[Venturi]

I wonder if the Devs would consider a 100 octane fuel modification once the pacific gets underway, changing the max manifold pressure as well as possibly changing the fuel gauge in the plane to a later one. That would account for both the early war period where the fuel wasnt really around, as well as the late war period where logistics and development caught up.

 

While the additive was a problem early in the P-40's life, 100+octane fuel was always available via Lend-Lease (since summer 41). After mid 1942, it seems obvious to me that the technical problems of the backfire screen had largely been fixed and there were no technical limitations to using higher MP. I suppose if you want to think about Battle of Moscow which is winter '41, this date is already past the point at which high octane fuel was delivered to the USSR under Lend-Lease from the USA. (deliveries started late Summer '41).

 

From June to the end of October 1941, $92 million worth of strategic goods were delivered from the United States. This sum included payment for 156,335 short tons of aviation gasoline, of which 25,185 tons were avgas with octane numbers above 99; 130,729 tons were avgas with octane numbers from 87 to 99; and 87,421 tons were avgas with octane numbers up to 87.

Alexander Matveichuk ,Ph. D. (History), Member, Russian Academy of Natural Sciences

 

 http://www.oilru.com/or/47/1006/

 

Most Russian engines required at least 87 octane to reach full boost potential. But in 1941-42, even lower octane rated fuels than 87oct were not being produced by the USSR in quantities necessary to operate high performance aircraft. In other words, if LaGGs are flying, it was because of access to higher-octane fuels, and it could be argued that these fuels were also from the USA - and where one octane from Lend Lease is available, another would be also.

 

 

...in 1940, an overwhelming proportion was avgas with low octane numbers of 70 to 74. This was almost good enough for obsolete domestically-produced aircraft, but only 4% of the demand for B-78 aviation gasoline, the best of those produced in the Soviet Union and the one needed by the new generation of warplanes, was satisfied across the country.

It was under unsatisfactory conditions such as these with regard to supplies of aviation gasoline that the Soviet airforce entered the initial phase of their Great Patriotic War on 22 June 1941.

Edited September 3, 2017 by Venturi

[Farky]

I wonder if the Devs would consider a 100 octane fuel modification once the pacific gets underway, changing the max manifold pressure as well as possibly changing the fuel gauge in the plane to a later one. That would account for both the early war period where the fuel wasnt really around, as well as the late war period where logistics and development caught up.

 

 

We already have P-40E with 100 octane fuel in game, engine limits will be lower with "low octane fuel".

 

 

Hardly 28gal worth of fuel spent there for "warmup". I agree less fuel will help the P-40.

 

 

I'm pretty sure that LukeFF is refering to Flight Operation Instruction Chart in P-40E manual, where is note - Allow 28 US gals.(23 Imp. gals.) for warm up, take-off and climb to 5000 feet altitude. Is it too much? It is, probably, for most cases. Allison V-1710-39 can with 28 US gals. run on Normal Rated Power (38.5 inHg @ 2600 rpm) for some 20 minutes for example.

 

 

I also think cutting out the extra 200lbs from design weight that have been added onto it in the sim would help as well.

 

 

Stop it, seriously. Nothing was added, weight of P-40E-1 in game is in accordance with most of the manuals and with actual weight measured in tests. Note - you don't need to show picture from 1941 manual, i know what are you talking about.

[Lusekofte]

 

 

Oh, this is the only flyable Hawk 81 there is, and it survived the attack on Pearl Harbor...

 

Actually the reason for it being here today was it was damage in pearl Harbor if I remember correctly, FlyPast followed its restoration 

[Cloyd]

EL,

 

I finally don't feel guilty about trying to talk you into buying the P40.

 

Cloyd

Edited September 3, 2017 by Cloyd

[BlitzPig_EL]

No worries Cloyd. 

 

LuseKofte, the way the pilot explained it was the aircraft was in a maintenance hanger for one reason or another when the attack came, it's why it survived.

 

None the less it was there at one of the pivotal moments in history, I can think of only one or two other aircraft that exist today that were there as well.

[LukeFF]

 

 

The P-40 still does not have animated bomb switches (although the panel has the cutouts for them). It is a real shame to not model "bomb arming" and "bombs on/off" switches, when the switch cut outs and placards are already there on the dash! It is a premium plane after all.

 

The P-40 D and E had the option for a mechanical or electrical bomb release system. That is most likely why you don't see those switches modeled and why, in the game, the bombs are armed via the handle on the floor of the cockpit.

[Royal_Flight]

EL, that's a great photo. And yeah, it looks massive, you don't get a sense of scale of them in relation to yourself in-game.

 

Also, am I alone in thinking that the Tomahawk/P-40B looks nicer than the E model? Or are there others...?

[216th_Lucas_From_Hell]

It really does look better.

[BlitzPig_EL]

I agree.

 

To me the iconic P40 will always be the Hawk 81, the plane that helped make the Flying Tigers famous.

[Venturi]

Stop it, seriously. Nothing was added, weight of P-40E-1 in game is in accordance with most of the manuals and with actual weight measured in tests. Note - you don't need to show picture from 1941 manual, i know what are you talking about. The Boscombe Down P-40 had all kinds of extra equipment added to it. You have not explained to my satisfaction how the Curtiss DESIGN weight is not correct to model all aircraft in the sim, but rather how ONE example of a RAF-contracted aircraft with all sorts of miscellaneous equipment in it is. Yes, I have read the report very thoroughly as you know. In fact, I am pretty sure I can come up with ANOTHER one-plane sample size example of a lesser weight... this is why the DESIGN weight should be used.

It really does look better.

 

And, the -B/C model is the one which is correct for Battle of Moscow, anyways.

The P-40 D and E had the option for a mechanical or electrical bomb release system. That is most likely why you don't see those switches modeled and why, in the game, the bombs are armed via the handle on the floor of the cockpit.

 

Thanks, I did not know that.

I agree.

 

To me the iconic P40 will always be the Hawk 81, the plane that helped make the Flying Tigers famous.

 

Have to say, the P-40B/C is really the one which saw a lot more of the "critical" action. It happened to look a lot better, and I actually liked the gun options better. 

 

I think the reason why the -E got the 6x 50cals, was because Curtiss was trying to sell the Brits P-40s, and they thought 2x 50cal and 4x 30cal wasn't sufficient.

In my opinion, the centerline 50s and lower rotational mass more than make up for switching out the 50s on the wings to 30 cals.

 

I'm pretty sure that LukeFF is refering to Flight Operation Instruction Chart in P-40E manual, where is note - Allow 28 US gals.(23 Imp. gals.) for warm up, take-off and climb to 5000 feet altitude. Is it too much? It is, probably, for most cases. Allison V-1710-39 can with 28 US gals. run on Normal Rated Power (38.5 inHg @ 2600 rpm) for some 20 minutes for example.

 

 

Just like everything else in that manual - conservative. Including the 90mph stall speed.

Edited September 3, 2017 by Venturi

[unreasonable]

<snip>

 

Also, am I alone in thinking that the Tomahawk/P-40B looks nicer than the E model? Or are there others...?

 

Not alone. Generally the earlier versions of a type look better to me than later ones, the Mk.I is the prettiest Spitfire, for instance. As you fit bigger engines to the original airframe and add various bits of equipment you get all sorts of nasty bulges.

Bf 109 series is the only exception that springs to mind.

[216th_Lucas_From_Hell]

Really? I find the 109 the perfect example of it - from neat little plane into the flying bulge that was the G6 and the Frankenmesser K. Matter of taste, I suppose.

 

The La-7 though looks much cleaner than the LaGG-3.

[unreasonable]

I was thinking in the 109 case that the Fs and early Gs look best, not the earlier versions: but I agree the very late ones look nasty.  

 

I would count the La-7 as a different plane to the LaGG-3 really: the in-line to radial switch is so significant.

[Jaws2002]

Well, I saw the former Duxford, now Collings Foundation Curtiss P40B today at Thunder Over Michigan.

 

 

And yeah, that's me.

 

I spoke with the pilot for a bit and asked him about how it is to fly.   He said it is very light and responsive on the controls, that it will out roll and out turn a P51, and out roll and probably out turn the Spit Mk IX he also pilots.

 

He also said it a wonderful airplane to fly, until the tailwheel touches the runway, then it turns into a monster... hehe.  Apparently cross winds are an issue for it on the ground.  I asked him about overheating, and he said it's not an issue in the air, but on start up or landing you have to either take off or shut it down really quickly, or it will over heat the coolant.

 

It was really fun to watch in flight,  it's pretty obvious just how effective the ailerons are on it.

 

Oh, this is the only flyable Hawk 81 there is, and it survived the attack on Pearl Harbor...

 

 

 

Oh, so that's what all the noise was about.

  I heard planes, across the river, over Detroit, all day yesterday, but I painted the house and couldn't even go out to see what planes were flying. 

 

P-40 is one a cool aircraft. Up close is pretty small compared to some other US planes. I've seen one fly in Forth Worth  next to an F-4U and the P-40 was tiny.

 

Congrats on a cool way to spend the weekend. 

[6./ZG26_Klaus_Mann]

 

 

  And yeah, that's me.

 

I respect your Beard.  

[6./ZG26_Klaus_Mann]

And FYI if you are flying the ingame P-40E at 37in and 2600rpm Auto Rich continuously, you are alread flying it at much higher Settings than prescibed. That's maximum Rated Power and shouldn't be used constantly, but apparently the Russians did nonetheless. 

 

When the Russians refer to their "much higher" Engine Settings they are talking about the Maximum Cruise of either

2300RPM and 30in either Auto Rich or Auto Lean,

2300RPM and 28in Auto- Rich or Lean and

Desired Cruise Setting of 2200RPM and 26in in Auto Lean. 

 

Some Manuals recommend

35in and 2500rpm as Max. Climb and

37in and 2400RPM as Max Cruise and

Normal Cruise at 30in and 2300RPM

 

As little as 2100RPM and 27in are recommended as Cruise. 

[Finkeren]

Not alone. Generally the earlier versions of a type look better to me than later ones, the Mk.I is the prettiest Spitfire, for instance. As you fit bigger engines to the original airframe and add various bits of equipment you get all sorts of nasty bulges.

Bf 109 series is the only exception that springs to mind.

How about the Yak-3? You'd be hard pressed to find a cleaner airframe in 1944.

[Guest deleted@83466]

And FYI if you are flying the ingame P-40E at 37in and 2600rpm Auto Rich continuously, you are alread flying it at much higher Settings than prescibed. That's maximum Rated Power and shouldn't be used constantly, but apparently the Russians did nonetheless. 

 

When the Russians refer to their "much higher" Engine Settings they are talking about the Maximum Cruise of either

2300RPM and 30in either Auto Rich or Auto Lean,

2300RPM and 28in Auto- Rich or Lean and

Desired Cruise Setting of 2200RPM and 26in in Auto Lean. 

 

Some Manuals recommend

35in and 2500rpm as Max. Climb and

37in and 2400RPM as Max Cruise and

Normal Cruise at 30in and 2300RPM

 

As little as 2100RPM and 27in are recommended as Cruise. 

 

The Power Settings as per the Official USAAF manual for P-40 with Allison Engine, 100 octane, are as follows:

 

Takeoff (Maximum) 52" (for 1 minute) 3000 rpm

Takeoff (Recommended)  45" (for 5 minutes) 3000 rpm

Climb (Maximum) 45.5 (for 5 minutes) 2600 rpm

Climb (Recommended) 35" 2500 rpm

Cruise (Maximum) 37.2" 2400 rpm

Cruise 30" (Recommended) 2300 rpm

 

I think we've already established that these are book values, that were regularly exceeded at the expense of mean TBO.  These are what I think were used as the "hard" limits by the developers when modeling the Allison engine.

 

I doubt that the Russians felt the need to exceed econ cruise power settings, as you state somewhat dogmatically.  I don't think this is the issue here.  Since I have an IQ over room temperature, I'm guessing that it was in combat in which they pushed it to the limits, and found that the engine was far more durable in practice than the values in the book.  I think there is a body of evidence to suggest that this is true.

Edited September 4, 2017 by Iceworm

[6./ZG26_Klaus_Mann]

I doubt that the Russians felt the need to exceed econ cruise power settings, as you state somewhat dogmatically.  I don't think this is the issue here.  Since I have an IQ over room temperature, I'm guessing that it was in combat in which they pushed it to the limits, and found that the engine was far more durable in practice than the values in the book.  I think there is a body of evidence to suggest that this is true.

 

I think it would have been a Combination of Flying between Rated Power, Military Power and the occassional WEP and not much less. 

 

But having an IQ just above Room Temperature would still make you less than even colossaly Stupid, mentally Retarded to the Extreme probably. an IQ of 21 is nothing to pride yourself with. You would barely be able to move with that IQ, much less Formulate an entire thought.

 

Unless of course your Room Temperature is just about the Boiling Point of Water, so I take it you are living in a Sauna. 

Edited September 4, 2017 by 6./ZG26_Klaus_Mann

[ZachariasX]

Fahrenheit, anyone?

[BlitzPig_EL]

[Venturi]

Fahrenheit, anyone?

 

How about the Yak-3? You'd be hard pressed to find a cleaner airframe in 1944.

Those are pretty birds. Pure pilot's planes and delights by all accounts. But, not the fastest or the highest climbing birds. 

[Farky]

The Boscombe Down P-40 had all kinds of extra equipment added to it. You have not explained to my satisfaction how the Curtiss DESIGN weight is not correct to model all aircraft in the sim, but rather how ONE example of a RAF-contracted aircraft with all sorts of miscellaneous equipment in it is. Yes, I have read the report very thoroughly as you know. In fact, I am pretty sure I can come up with ANOTHER one-plane sample size example of a lesser weight... this is why the DESIGN weight should be used.

 

 

Numbers from that data sheet are CALCULATED (i.e. theoretical), actual weight of P-40E was simply higher.

 

Standard weight of P-40E-1 in game - 3819.1 kg ( 8420 lbs.). Standard weight is in this case airplane with full fuel + 1410 rounds of ammunition.

 

Standard weight of P-40E according VVS manual - 3819.6 kg ( 8421 lbs.). In manual is 3840 kg, but with 1560 rounds of ammunition (weight 212 kg).

 

Standard weight of P-40E (No. 40-384) according USAAF report - 8434 lbs.. Weight without ammunition in that report is 8011 lbs., 1410 rounds of ammunition weights 423 lbs.. - http://www.wwiiaircraftperformance.org/P-40/P-40E_40-384_PHQ-M-19-1300-A.pdf

 

Standard weight of P-40E (No. 40-633) according USAAF report - 8458 lbs.. Weight without ammunition in that report is 8035 lbs., 1410 rounds of ammunition weights 423 lbs.. - http://www.wwiiaircraftperformance.org/P-40/P-40E_40-633_FS-M-19-1580-A.pdf

 

Standard weight of P-40E-1 according Boscombe Down report - 8408 lbs.. This is measured weight, not theoretical. And there is no extra equipment, it is standard P-40E-1.

 

Conclusion - weight of P-40E-1 in game is on point.

 

----------

 

 

Just like everything else in that manual - conservative. Including the 90mph stall speed.

 

 

Why do you think that 90 mph stall speed is conservative?

[Max_Damage]

I ve been flying this plane with pleasure since i have bought it a few days ago. You want someone watching your 6 (or be in red TS). Three me109 in one flight, another two 110s the other day. Super powerful weapons on this plane and unlimited ammo. The guns really compensate for a lot of drawbacks.

 

76-78% throttle 70% RPM nominal mode(max cont.)

 

70% throttle 100% RPM combat mode( 5 minutes + random amount).

 

You can fly it with canopy open to be able to watch your 6 much much better. And use the bomb when available.

Edited September 4, 2017 by Max_Damage

[chris455]

I agree.

 

To me the iconic P40 will always be the Hawk 81, the plane that helped make the Flying Tigers famous.

I'm one of those weirdos that typically regards the early models of anything as being the best looking/sexiest/most interesting. You can see the fullfilment of the designers dreams and intentions unadulterated by later modifications by those of unwashen hands.

The Hawk 81 is no exception, even though later marks still had a certain rugged beauty. 

To me, the 81 is pure Americana, little different from a '63 Corvette or '57 T-Bird. 

[Blooddawn1942]

The P-40 is very enjoyable now. Thanks for revisiting!

[Multimetal]

One thing that I'm confused about is the prop RPM control on the P40 in-game.  As I understand it, the constant speed unit should keep the prop RPM the same regardless of manifold pressure, for instance if you were setting up the engine for a steady climb you would set the pressure to 30-35in with the throttle and use the prop control to set the rpm in the 24--2500 range.  The constant speed unit should keep the prop RPM the same even as you lose manifold pressure in the climb, due to altitude.  However, unless I'm doing it wrong, on the P40 in-game the RPM seems to be controlled by the switch on the instrument panel, the prop control on the throttle quadrant doesn't move and increasing or decreasing the prop RPM with the electric switch changes the manifold pressure too, which makes setting cruise pressure and climb pressure difficult.  Am I doing this right?  I believe on the real-life P40 the prop RPM could be adjusted with either the switch or the lever at the pilot's discretion, is this modeled in the game?

[LukeFF]

The electrical switch was only to be used in case the constant speed unit failed, hence it doesn't really have a lot of usefulness in the game.